Propane fumigation works fine on IDI type diesels and direct injection. I've seen it on GM 6.2-6.5's and Ford 7.3's.... The higher compression engines like the GM's don't seem to like the propane as much as others. The higher the compression the smaller the combustion area and the more fine the line between acceptable and exceeding peak combustion pressure limits.... Head gasket time!! Propane is not as volatile as ether or acetylene, it won't burn until the diesel is injected. While this certainly do-able on a MB, the cheapest propane kit I have seen is @$500, and then you need an approved tank, installation, etc. I don't see the cost benefit. RT